
def _prep_msg(msg):
    """Turn msg into a rendered image and center text on the button."""
    msg_image = font.render(msg, True, self.text_color, self.button_color)
    msg_image_rect = msg_image.get_rect()
    msg_image_rect.center = self.rect.center
    return msg_image, msg_image_rect
def draw_button(self):
    # Draw blank button and then draw message.
    self.screen.fill(self.button_color, self.rect)
    self.screen.blit(self.msg_image, self.msg_image_rect)
